Many environmental toxicants, such as heavy metals, solar radiation, pesticides, and chlorinated aromatic hydrocarbons like dioxins, modulate cellular processes that often result in disruption of redox homeostasis. Aberration in redox homeostasis causes accumulation of reactive oxygen species (ROS) and ROS has been causally associated with genome instability, cell death, alterations in gene expression and inflammatory responses. Increased oxidative stress is associated with numerous autoimmune diseases and may have a contributing role in some neurodegenerative conditions. The molecular mechanisms by which ROS induces cellular responses are multivariable in nature and have not yet been clearly delineated. Moreover, the pathways and mechanisms by which ROS ultimately contributes to disease including respiratory disease like asthma, neurological disorders and cancer remain largely elusive. The Oxidative Stress Research Initiative is comprised of a multidisciplinary group of scientists that use numerous models including Drosophila, genetically engineered mice, yeast and human cells to study oxidant stress and its cellular manifestations. The initiative is led by Dr. Jun Tsuji, PhD, Professor in the Dept of Environmental and Molecular Toxicology.